Objective To study the changes in and correlations between the partial pressure of end-tidal carbon dioxide (PETCO2) and the coronary perfusion pressure during cardio-pulmonary resuscitation (CPR) based on the cardiac arrest dog models of ventricular fibrillation by electric shock. Methods 36 healthy dogs were evenly randomized into 3 groups including 4 minutes close-chest CPR(CCCPR) group, 4 minutes open-chest CPR(OCCPR) group, and 8 minutes OCCPR group. There were 12 dogs in each group, half male and half female. In the process of CPR, all parameters about PETCO2 and CPP were recorded. Results In the 4 minutes CCCPR group, the correlation coefficient between the CPP and the PETCO2 was 0.992 (P<0.05), which was in positive linear correlation. In the 4 minutes OCCPR group, the correlation coefficient between the CPP and the PETCO2 was 0.937 (P < 0.05), which also showed positive linear correlation. In the 8 minutes OCCPR group, the correlation coefficient between the CPP and the PETCO2 was 0.952 (P<0.05), and was also in positive linear correlation. The percentage of ROSC was 66.7(8/12) in the 4 minutes CCOPR group, 100%(12/12) in the 4 minutes OCCPR group and 58.3%(7/12) in the 8 minutes OCCPR group. There were statistical differences in CPP, PETCO2 between models with ROSC and without ROSC at 1, 2, 5, 10, 15 and 20 mins of CPR (all P<0.05). Conclusions This research shows that there is a close positive linear relationship between the coronary perfusion pressure and the PETCO2, and PETCO2 could be used to evaluate the prognosis of the CPR.

Objective To investigate the retinal nerve fiber layer (RNFL) thickness of anisometropic amblyopic children with Littmann-adjusted OCT examination method. Methods A total of 30 anisometropic amblyopic subjects (4 to 14 years old) without treatment were enrolled, whose amlyopic eyes were amlyopic eye group and fellow eyes were fellow eye group. Also 50 emmetropic children′s right eyes were enrolled into normal group. Retinal nerve fiber layer thickness were obtained with optical coherence tomography (OCT), then were adjusted by Littmann formula. Each group was compared with other two groups specificly. Results Amblyopic eye group had no significant difference with other groups in each regions of RNFL ( P > 0 . 05 ) , both before and after Littmann-adjusted. The RNFL of amblyopic group group in T、 TI、 NI、 N regions had significant correlation with eye axis length before adjust(P < 0.05), while only T and NI had significant correlation after adjust (P<0.05). Conclusions The RNFL thickness of anisometropic amblyopic eyes had no significant difference with fellow eye and normal eye. Every research of RNFL thickness must consider the measurement error induced by eye axis length.